On a dry road, a car with good tires may be able to brake with a constant deceleration of 5.93 m/s^2. (a) How long does such a car, initially traveling at 27.9 m/s, take to stop? (b) How far does it travel in this time?

Question

anonymous · Answer

a is 4.7s?

anonymous · Answer

and b? not sure which formula to use

anonymous · Answer

t=4.7s
distance appx 65.56
distance =average spped* time

anonymous · Answer

ohhh but wouldn't you take into account the acceleration? i thought you would have to use a motion formula...

anonymous · Answer

of some sort

anonymous · Answer

average spped here i used for the acceleration is constant

anonymous · Answer

yeh thats right

anonymous · Answer

ok so acceleration is not taken into account when there is time and speed if it is constant...ok just feels like it would stop sooner than that distance

anonymous · Answer

oh no u have to take the avrage of initial and final speed and then multiply it with time as long as acc/retard is constant

anonymous · Answer

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